Podrían explicarme el 'se' en:

'Se me cae la cara de la vergüenza'
'Se me perdió la billetera'

Gracias

See a translation

@aacunaamelia

Your profile tells me that you're very good at English, so perhaps take a look at my explanation - and promise not to be offended if I sometimes state the obvious!!

'Se me cae la cara de la vergüenza' = My face drops from shame
(we say 'I hang my head in shame')


We have two options when we want to say 'drop/fall' - either 'caer', or its pronominal form 'caerse'.

According to the Internet, there is very little difference between them, except that 'caer' is used to describe a simple fall/drop - 'it fell'; whereas 'caerse' is used when more information is supplied (as is the case here: 'de la vergüenza').
So 'caerse' is preferred (me caigo, te caes, se cae etc.)

The 'me' is a dativo ético/dativo de interés.

'Cara' is the subject of the sentence ('caer' is an intransitive verb: it doesn't create any object; neither direct nor indirect).

So this is what I believe to be the case.
That 'se' is the pronoun belonging to the verb 'caerse', and since the dativo ético cannot be left out in this phrase, more correctly 'caersele'.

****************************

Se me perdió la billetera

We English speakers love this one!
It's an example of what we call the 'no fault' or 'accidental' se.
The wallet was lost, but we are not 100% responsible for the loss.

Perdió - it lost (perder)
Se perdió - it got lost (perderse) Note: passive in meaning.
Se me perdió - it got lost on me (perdersele)

So the verb in use is 'perdersele', which is a combination of a pronominal verb (perderse), plus a dativo ético/dativo de interés (which in English often translates to 'on me', 'by me' or 'for me'; Mi niño no me come - my child won't eat for me)

So 'Se me perdió la billetera' = the wallet got lost on me - it was accidentally lost, whereas with 'Perdí la billetera' I'm admitting that I lost the wallet - it was entirely my fault.
So you can see why we call it 'the no-fault se'.

Because both your examples have objects (cara & billetera) as the subject of a pronominal verb, 'se' is used as the pronoun.
Even when plural, it's still 'se' (me, te, SE, nos, os, SE)

Se me perdieron las entradas.

If I have made any mistakes, I'd appreciate any feedback.